Parallel jaw pliers



A. WEISENBURGER PARALLEL JAW PLIERS 2 Sheets-Sheet 1 Filed Oct. 26, 1954 FIG-7 W, .vvvmmw .F

- wks/vrap w W Oct- 9, 1956 A. WEISENBURGER PARALLEL JAW PLIERS 2 Sheets-Sheet 2 mmmrae Filed 001;. 26, 1954 Unite States Patent PARALLEL JAW PLERS August Weisenburger, Frankfurt am Main, Germany Application October 26, 1954, Serial No. 464,680

2 Claims. (Cl. 81-515) The present invention relates to pliers, to be used preferably in the shape of flat-pliers, and devised in such a way that the jaws of the pliers are caused to open and close parallel to each other.

In known pliers of this kind, the parallel guidance of the jaws is effected with the aid of guide-channels provided at downwardly projecting portions of the jaws, and by means of which the jaws are, during the opening and closing of the pliers, guided at guide-members provided at the handles of the pliers.

From these known constructions, the pliers of the invention differ in that the jaws of the pliers terminate, at the ends facing the handles of the pliers, in guide-pins guided in perforated bolts rotatably arranged in the handles of the pliers beneath the joint-pin of the pliers.

A construction of this type permits the manufacture of all of the parts of the pliers in a stable and sturdy way, that is to say, either in a swage through forging, or through forming by means of pressing or casting (malleable cast iron), whereby the stability of the pliers is considerably increased as compared with pliers which have their handles formed from sheet-iron.

Additional features and advantages of the invention will be understood from a consideration of the following detailed description taken in connection with the accompanying drawings, forming a part of this specification and in which an embodiment of the invention has been shown by way of example. However, I wish to say that the invention is not confined to any strict conformity wth the showing of the drawings, but may be changed or modified, so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appending claims.

In the drawings, in which like parts are referred to by the same reference numerals,

Fig. 1 is a view of the closed-up pliers;

Fig. 2 is a sectional view of the pliers of Fig. 1;

Fig. 3 is a view of the pliers in opened-up condition;

Fig. 4 is a vertical section on line IV-IV of Fig. 2;

Fig. 5 is a horizontal section on line V-V of Fig. 2;

Fig. 6 is a diagrammatic illustration of the closed-up pliers;

Fig. 7 is a diagrammatic illustration of the opened-up pliers.

Referring now to the drawings in detail, the pliers consist of a pair of double-armed levers arranged crosswise on top of each other in scissors-like fashion. The longer arms 1 and 2 of the levers serve as handles, while to the shorter arms 3 and 4 of the levers, the jaws 5 and 6 provided in their confronting inner side faces with the recesses 9 and 10 for the arms 3 and 4 to engage in, are pivotally secured by means of the pivots 7 and 8. From the lower ends of the jaws 5 and 6 project guide-pins 11 2,765,689 Patented Oct. 9, 1956 and 12 guided for displacement parallel to each other in perforations of guide bolts 13 and 14 rotatably mounted in the handles 1 and 2 in the cavities 15 and 16 of the latter. Provided at the abutting portions of the handles 1 and 2, beneath the joint-pin 17, are cutting edges 18 and 19.

The device works as follows:

When the pliers are moved from closing position (see Fig. 6) to opened-up position (see Fig. 7), the handles 1, 2 and the short arms 3 and 4 of the levers move on circular arcs in outward direction, whereby the jaws 5, 6, pivotally secured to the bolts 7, 8, move away from each other, but always keep up their parallel position with respect to each other, because of the guidance of their guide-pins 11 and 12 in the rotatable perforated guide bolts 13 and 14, while, on the other hand, the distance between the points 7, 13 and 8, 14 decreases. As the perforated guide bolts 13 and 14 are open at their lower sides, the guide-pins 11 and 12 are enabled to traverse the perforated guide bolts and to project from the latter in downward direction within the cavities 15, 16 of the bandles 1, 2. In addition to this the angles between the handies 1, 2 and the guide-pins 11 and 12 will change when the handles are moved, which change of the angles, however, is taken care of by the provision of the perforated rotatable guide bolts 13 and 14. While the angle between the guide-pins 11, 12 and the axis of the perforated guide bolts 13, 14 remains constant, the angle between the guidepins 11, 12 and the handles 1, 2 changes in conformity with the degree of opening of the pliers. The handles 1, 2 will then perform a slight rotary movement about the perforated guide bolts 13, 14.

The pivots 7 and 8 and the rotatable perforated guide bolts 13 and 14 are so arranged that the distance of the guide bolts 13 and 14 from the joint-pin 17 exceeds in length the distance of the pivots 7 and 8 from the jointpin 17, so that during the opening and closing of the jaws the bolts 13 and 14 effecting the parallel guidance of the guide-pins 11 and 12 move on an arc of larger radius than the pivots 7 and 8 (see Figs. 1 to 3).

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Parallel pliers, comprising a pair of levers provided each with a longer and a shorter lever-arm, said levers pivotally joined together between said longer and shorter lever-arms in scissor-like fashion and provided in each of said longer lever-arms in the proximity of said lever pivot-joint with a cavity, an apertured guide-bolt rotatably mounted within and transversely extending through said cavity; and a pair of jaws, each provided with an abutting inner face having a recessed portion within which a free end of one of said shorter lever-arms is pivotally fastened, said pair of jaws terminating at corresponding ends in a pair of cylindrical parallel guide-pins extending into respective cavities of said longer lever-arms and through the respective apertures of said rotatable guidebolts for shiftable parallel guidance therein.

2. Parallel pliers, as set forth in claim 1, in which said rotatable apertured guide-bolts are spaced from said lever pivot-joint a distance that exceeds in length the distance of the pivot points of said shorter lever-arms from said lever pivot-joint.

References Cited in the file of this patent UNITED STATES PATENTS 

